package com.example.tests;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import com.thoughtworks.xstream.XStream;

public class GroupDataGenerator {

  public static void main(String[] args) throws IOException {
    if (args.length < 3) {
      System.out.println("Please specify parameters: <amount of test data> <file> <format>");
      return;
    }

    int amount = Integer.parseInt(args[0]);
    File file = new File(args[1]);
    String format = args[2];

    if (file.exists()) {
      System.out.println("File exists, please remote it manually: " + file);
      return;
    }
    
    List<GroupData> groups = generateRandomGroups(amount);
    if ("csv".equals(format)) {
      saveGroupsToCsvFile(groups, file);
    } else if ("xml".equals(format)) {
      saveGroupsToXmlFile(groups, file);
    } else {
      System.out.println("Unknown format " + format);
      return;
    }
  }

  private static void saveGroupsToXmlFile(List<GroupData> groups, File file) throws IOException {
    XStream xstream = new XStream();
    xstream.alias("group", GroupData.class);
    String xml = xstream.toXML(groups);
    FileWriter writer = new FileWriter(file);
    writer.write(xml);
    writer.close();
  }

  public static List<GroupData> loadGroupsFromXmlFile(File file) {
    XStream xstream = new XStream();
    xstream.alias("group", GroupData.class);
    return (List<GroupData>) xstream.fromXML(file);
  }

  private static void saveGroupsToCsvFile(List<GroupData> groups, File file) throws IOException {
    FileWriter writer = new FileWriter(file);
    for (GroupData group : groups) {
      writer.write(group.getName() + "," + group.getHeader() + "," + group.getFooter() + ",!" + "\n");
    }
    writer.close();
  }

  public static List<GroupData> loadGroupsFromCsvFile(File file) throws IOException {
    List<GroupData> list = new ArrayList<GroupData>();
    FileReader reader = new FileReader(file);
    BufferedReader bufferedReader = new BufferedReader(reader);
    String line = bufferedReader.readLine();
    while (line != null) {
      String[] part = line.split(",");
      GroupData group = new GroupData()
        .withName(part[0])
        .withHeader(part[1])
        .withFooter(part[2]);
      list.add(group);
      line = bufferedReader.readLine();
    }
    bufferedReader.close();
    return list;
  }

  public static List<GroupData> generateRandomGroups(int amount) {
    List<GroupData> list = new ArrayList<GroupData>();
    for (int i = 0; i < amount; i++) {
      GroupData group = new GroupData()
        .withName(generateRandomString())
        .withHeader(generateRandomString())
        .withFooter(generateRandomString());
      list.add(group);
    }
    return list;
  }

  public static String generateRandomString() {
    Random rnd = new Random();
    if (rnd.nextInt(3) == 0) {
      return "";
    } else {
      return "test" + rnd.nextInt();
    }
  }
}
